1. Field
Embodiments of the present disclosure generally relate to the evaluation of semiconductor lasers. More specifically, the embodiments relate to systems and methods of evaluating the optical output of visible light sources comprising a wavelength conversion device and a semiconductor laser having a gain section, a wavelength selective section, and a phase section.
2. Technical Background
Semiconductor lasers, such as distributed Bragg reflector (DBR) lasers, are being utilized in an increasing number of applications. For example, semiconductor lasers capable of producing optical radiation in the red, blue and green optical spectrums may be incorporated into a laser projector to produce scanned laser images. However, wavelength thermal drift and cavity mode-hopping in semiconductor lasers may adversely affect optical output power and create noticeable defects in the scanned laser image produced by laser scanner system (particularly those emitting wavelength-converted optical radiation in the green spectral range). Therefore, some semiconductor laser packages are driven by a high frequency modulated gain current to minimize the effect of wavelength thermal drift and cavity mode-hopping in the image. However, the complicated electronics necessary to produce such high frequency gain currents are not cost effective or easily implemented into testing procedures of high-volume production environments. For example, high-frequency, high-gain current gain drive signals may require that the test equipment be located very close to the laser under test and may also produce significant electrical noise. Further, the high-frequency, high-gain current gain drive signals may necessitate soldered connections of the laser under test to the evaluation equipment, which may be unacceptable in a high-volume production environment.
Accordingly, a need exists for alternative systems and methods for evaluating visible light sources.